Back Firing

[r33bob]

hey

my r33 gtst after it has warmed up, starts to backfire when you stop accelerating

would this be using like much more fuel and or what would be casuing it to do this?

[mad082]

do you have an atmo bov?

and yes it would be using more fuel, but not very much.

[r33bob]

nah its all standard except for the exhaust on it....

do u reckon it could be the o2 sensor?

[mad082]

could be o2 sensor, or it could be an exhaust leak. generally if there is an exhaust leak (more than likely just after the turbo) it sucks ait back in and backfires. my mates old EB falcon had cracked headers and it would shoot flames out the back when he backed off until he got them fixed...... but his cat was empty too.

[r33rb26ett]

its to do with nissans rich as air/fuel ratios. once you back off it dumps the excess fuel in to the exhaust and BANG!. an aftermarket computer like an apexi power fc will fix most of this up as its tuned to run leaner

[mad082]

thats not very accurate.

if you are running rich and your spark plugs are working fine then it should still burn all the fuel dumped in.

try putting new plugs in and see what that does. mine used to pop, and stall ocassionally on decel after full throttle high rpm runs. put some new plugs in and it went away.

[r33bob]

thanks when i get some spare cash and time i will try it